Killer bees! Insects help armies wage war

Q.You know about warring humankind “letting loose the dogs of war," but how about "the bugs of war"? –D. Petraeus

A. Fifty years ago, following the launch of the Soviet satellite Sputnik, the U.S. Department of Defense formed the Defense Advanced Research Project Agency (DARPA), which developed stealth aircraft and an early version of the Internet, says Amy Stewart in Wicked Bugs: The Louse That Conquered Napoleon's Army & Other Diabolical Insects.

These days, DARPA researchers have also turned their attention to insects, seeking to implant computer chips inside caterpillars before they metamorphose into moths or butterflies so they can be directed into enemy locations to transmit intelligence without detection.

Interestingly, bees and wasps have been used as weapons for thousands of years. In ancient times, hurling a beehive or wasp nest at an enemy was an effective way to wreak havoc and send even fierce warriors running. Early Greek writings on warfare described the practice of building tunnels under enemy walls and releasing the bugs there. Also, the use of catapults to hurl hives over enemy walls goes back at least to Roman times, continuing through the Middle Ages.

Q.In the "race" for global communication penetration, one of the contestants was the "tortoise" and one the "hare." Can you guess what these animals symbolize? –A. Gore

A. As a column reader, you are almost surely one of the world's 1.5 billion Internet users, or a hare. It took the tortoise-like telephone seven decades to go from 1 to 75 percent penetration of North American households, says David G. Myers in Social Psychology. Yet access to the Internet reached the 75 percent figure in only about seven years. Half of European Union citizens, 3 in 4 Americans, and more than 4 in 5 Canadians and Australians enjoy e-mail and web surfing, according to internetworldstats.com.

Q.When I lift my wife for a good hug, her weight seems vastly different depending on whether she's limp or rigid. Is there anything real here, or is it my imagination? I noticed the same thing a few years back when I'd carry our kids to bed.–R. Gosling

A. When you lift something (or someone), much of the work is done by a few major muscles such as the biceps, New York physicist Spencer Weart toldNew Scientist magazine. But dozens of smaller muscles that help in adjusting how you balance the load are often less well developed and so tire quickly.

"A rigid load is easier to balance, but something limp will shift around, putting more strain on the smaller muscles as you readjust,” Weart wrote. “This is why weight lifters pick up dumbbells, not sacks of ball bearings."

Q.What's it take to "defy gravity" on an amusement park roller coaster? –B. Bailey

A. Designing a good roller-coaster loop is a balancing act, with the coaster naturally slowing as it rises against gravity but still needing to move fast enough to clear the crest, says Julie Rehmeyer of Wired magazine. The curving track creates a "centripetal force," causing the cars to accelerate toward the center of the loop, while momentum sweeps them forward. This acceleration gives the ride its visceral thrill but puts stress on the fragile human body.

For instance, Coney Island's Flip-Flap Railway, built in 1895, reached a neck-snapping 12 times the force of gravity at the bottom of its loop, more than enough to induce what pilots call G-LOC, or gravity-induced loss of consciousness. In other words, riders often passed out. So modern designers adapted an upside-down teardrop shape called a clothoid, where the track curves more sharply up top than at the bottom. Now most of the turn happens at the peak, where speed and acceleration are diminished.

Result: no G-LOC, just screams!~ Send Strange questions to brothers Bill and Rich at strangetrue@cs.com